#include<iostream>
#include<stdlib.h>
#include<stdio.h>
using namespace std;
#include<string.h>

int main(int argc, char *argv[])
{
    if(argc != 2)
    {
        cout<<"Usage: "<< argv[0] << "-[a|b|c|d]"<<endl;
    }
    else if(strcmp(argv[1],"-a")==0)
    {
        cout<<"function1"<<endl;
    }
    else if(strcmp(argv[1],"-b") == 0)
    {
        cout<<"function2"<<endl;
    }
    else if(strcmp(argv[1],"-c")== 0 )
    {
        cout<<"function3"<<endl;
    }
    else if(strcmp(argv[1],"-d") == 0)
    {
        cout<<"function4"<<endl;
    }

   // int i = 0;
   // for(;i<argc;i++)
   // {
   //     printf("argv[%d]->%s\n",i,argv[i]);
   // }
    return 0;

}
